The use of organic cationic fabric softeners is known. Blomfield in U.S. Pat. No. 3,095,373 discloses cationic chemical compounds having at least one hydrophobic chain having at least 16 carbon atoms for use as softening agents for laundered fabrics.
The use of clays as softening agents is also known. A number of kinds of clay have been suggested for use in detergent compositions for many years, for example, British Pat. Nos. 401,413, Mariott, accepted Nov. 16, 1933 and 461,221, Marriott et al, accepted Feb. 12, 1937 disclose the use of colloidal bentonite in synthetic detergent compositions, built or unbuilt, intended for the washing of hair, textiles, or hard surfaces. More recently British Pat. No. 1,400,898, Storm and Nirschl, sealed Nov. 19, 1975 disclosed the use of certain smectite clays in built detergent compositions to provide through-the-wash fabric softening, and British Pat. No. 1,401,726, Ohren, sealed Nov. 25, 1975 disclosed the use of those clays in soap compositions containing a minor amount of synthetic detergents as curd dispersants. Other prior art references have disclosed the use of clay in washing compositions to provide other benefits, such as builder, water-softener, anticaking agent, suspending agent, soil release agent, hair fulling agent, and filler.
The use of clay and organic cationic fabric softening ingredient combinations in detergent compositions for the simultaneous purpose of cleaning and softening fabrics, in addition to other auxiliary benefits, such as static control, is also known. Bernardino in U.S. Pat. No. 3,886,075 discloses compositions comprising particular smectite clays, cationic anti-static agents and certain substituted amino compatibilizing agents which are detergent compatible and provide softening and antistatic benefits to fabrics washed therein. Speakman in U.S. Pat. No. 3,948,790 discloses detergent compositions containing short chain quaternary ammonium clays which are effective in providing fabric softening with non-ionic detergents.
In general, it has been recognized that while certain clays do provide fabric softening, such softening is of a dry character and limited in softening ability in relation to the more conventional organic cationic fabric softener.
Organic cationic softening agents provide a desirable soft and lubricious feel to the fabrics but their use is typically limited to those chemicals that are readily soluble/dispersible in the homemaker's laundering process and have an affinity for fabric deposition. The organic cationic softening chemicals meeting these criteria tend to be incompatible with anionic surfactants and thus have generally been employed in the rinsing laundering process or in the mechanical dryer. Softening performance in the rinsing process because of this incompatibility is likely to be a function of the anionic detergents carried over from the wash process, and this is likely to be variable.